Showing papers by "Pantazis Mouroulis published in 2010"

Optical design, performance, and tolerancing of next-generation airborne imaging spectrometers

Abstract: We describe the optical design and performance of the Next-Generation airborne Imaging Spectrometer (NGIS) currently being constructed at Caltech's Jet Propulsion Laboratory. The new, high-resolution instrument incorporates a number of design advantages including a two-mirror anastigmatic telescope for simplified alignment and high throughput, as well as a concentric, multi-blazed grating for tailored broadband efficiency. A detailed tolerancing and sensitivity approach reveals tight requirements that must be satisfied for spectral calibration and boresight stability. This improved spectral and pointing stability, combined with high uniformity and high signal-to-noise ratio allows us to generate spectrometry measurements capable of answering challenging science questions.

Polarization and stray light considerations for the Portable Remote Imaging Spectrometer (PRISM)

Abstract: The Portable Remote Imaging Spectrometer (PRISM) is a pushbroom imaging spectrometer currently under development at the Jet Propulsion Laboratory, intended to address the needs of airborne coastal ocean science research. The distinguishing characteristics of the design are high signal to noise ratio, high uniformity of response, and low polarization sensitivity. The optical design is based on the Dyson spectrometer. We discuss here design refinements that are critical for stray light control and for reducing the polarization sensitivity of the entire instrument to below 2%.

Design of an Airborne Portable Remote Imaging Spectrometer (PRISM) for the coastal ocean

Abstract: PRISM is a pushbroom imaging spectrometer currently under development at the Jet Propulsion Laboratory, intended to address the needs of airborne coastal ocean science research We describe here the instrument design and the technologies that enable it to achieve its distinguishing characteristics PRISM covers the 350-1050 nm range with a 31 nm sampling and a 33(deg) field of view The design provides for high signal to noise ratio, high uniformity of response, and low polarization sensitivity The complete instrument also incorporates two additional wavelength bands at 1240 and 1610 nm in a spot radiometer configuration to aid with atmospheric correction

Field calibration of a broadband compact thermal infrared spectrometer for earth science

Abstract: We present field results showing excellent performance for a compact earth observing thermal infrared (EOTIR) hyperspectral grating spectrometer using a combination of a Quantum Well Infrared Photodetector (QWIP) and grating based Dyson spectrometer. 12The Dyson design allows for a very compact and optically fast system (F/1.6). Cooling requirements are minimized due to the single monolithic prism-like grating design. The configuration has the potential to be the optimal sciencegrade imaging spectroscopy solution for lighter-than-air (LTA) vehicles and unmanned aerial vehicles (UAV) due to its small form factor and relatively low power requirements. The QWIP allows for optimum spatial and spectral uniformity and provides adequate responsivity to allow for near 100mK noise equivalent temperature difference (NEDT) operation across the EOTIR passband. These tests are in preparation for the deployment of the Hypserspectral Thermal Infrared Spectrometer (HyTES) which is currently being funded under NASA's instrument incubator program (IIP). Test results show NEDT, linearity as well as applicable earth science emissivity target results (silicates, water) measured in direct sunlight. A calibration is also performed to derive direct water temperature using a well calibrated transfer radiometer operating simultaneously.